A new zero-voltage and zero-current-switching (ZVZCS) full-bridge (FB) pulsewidth modulation (PWM) converter is proposed to improve the performance of the previously presented ZVZCS FB PWM converters. By adding a secondary active clamp and controlling the clamp switch moderately, ZVS (for leading-leg switches) and ZCS (for lagging-leg switches) are achieved without adding any lossy components o...

With the rapid development of wide-band gap semiconductor chip and package technologies, voltage class commercial silicon carbide (SiC) device is gradually improved. This paper concentrates on latest 3.3-kV full SiC-based metal oxide field-effect transistor (MOSFET) its application in railway traction. First, compared with Si-based insulated-gate bipolar (IGBT), MOSFET shows lower switching los...

A circuit configuration of a single-phase nonisolated online uninterruptible power supply (UPS) with 110-V/220-V input–output voltage ratings is proposed, allowing the bypass operation without a transformer even if the input voltage is different from the output voltage. The converter consists of an ac–dc/dc–dc three-level boost converter combined with a double half-bridge inverter. In this type...

A bidirectional converter (BDC) is required in areas where generated energy is stored. Some of the application areas are uninterruptible power system, transportation,, flywheel energy storage systems, etc. Bidirectional flow of power using buck mode and boost mode along with efficiency and high power density is important need of such systems. This report proposes a new topology of BDC with the ...

This paper presents an investigation of a voltage and frequency controller for an isolated asynchronous generator (IAG) driven by a wind turbine and supplying 3-phase 4-wire loads to the isolated areas where a grid is not accessible. The control strategy is based on the indirect current control of the VSC (voltage source converter) using the frequency PI controller. The proposed controller cons...

Two standard commercial flashlamp-pumped Nd:YAG (YAG denotes yttrium aluminum garnet) lasers have been upgraded to "pulse-burst" capability. Each laser produces a burst of up to 15 2 J Q-switched pulses (1064 nm) at repetition rates of 1-12.5 kHz. Variable pulse-width drive (0.15-0.39 ms) of the flashlamps is accomplished by insulated gate bipolar transistor (IGBT) switching of electrolytic cap...

This paper is proposed to improve the efficiency of the series resonant inverter for industrial heating applications. Resonant inverters are those operate at high frequency with reduced losses preferable for induction heating. Resonating components and switching device which are placed in series to load forms series resonant inverter. Inverter which is characterized by full bridge made up of In...

We present the design of a modular, robust, high-current switch for controlling discharge current in the large plasma device ~LAPD! at UCLA. As developed, 10 insulated gate bipolar transistor units are connected in parallel to provide 24 kA current-carrying capacity. Associated snubber and protection circuits are described in detail. The switch is typically operated at a 1 Hz repetition rate, w...

With the advance of insulated gate bipolar transistor (IGBT) converters, Multi-Terminal DC (MTDC) based on the voltage-source converter (VSC) has developed rapidly in renewable and electric power systems. To reduce the copper loss of large capacity and long distance DC transmission line, an improved droop control design based on optimal power sharing in VSC-MTDC integrating offshore wind farm i...

Based on extremely uneven temperature distribution along the insulated gate bipolar transistor (IGBT) chip vertical path during switching transients, a short-duration transient microsecond-scale prediction model applicable to multi-timescale simulation is presented in this paper. Traditional thermal models often take active area as uniform heat source obtain victual junction (Tvj). In paper, di...